Each of the foregoing patents and patent applications generally discloses systems wherein a mobile vehicle transponder unit is associated with a vehicle and communicates with one or more fixed transceiver units at one or more locations, exchanging and updating individual status information, as the vehicle moves. The information is generally account information, although in the case of Ser. No. 945,534 this is primarily vehicle-specific load status, measurement, route or other evolving information. In the present invention, the information is debit account toll information, and communications between the vehicle transponder, also referred to as an in-vehicle component or xe2x80x9cIVC,xe2x80x9d occur at or near the toll collection stations located along a route.
This invention relates generally to systems for vehicle toll collection, and, more particularly, relates to apparatus and methods for automatic, non-contact, high-speed collection of vehicular tolls.
An increasing number of vehicles are traveling over progressively more congested highways. The collection of tolls by conventional means has had a negative effect upon highway throughput and safety. Congestion and long backups on toll plazas are becoming more common. Such conditions involve a significant economic cost, through lost time, and reduced productivity. Moreover, serious accidents at toll plazas, caused by operator or mechanical failure, have also increased in frequency.
Certain toll authorities have attempted to respond to these problems by providing coin-operated toll collection devices, or by instituting a toll-plate system in which toll-takers visually inspect each incoming vehicle for an appropriate toll plate or sticker. Coin-operated toll collection systems, however, do little to increase throughput, and are susceptible to fraud, through the use of counterfeit coins. Toll-plate systems suffer the same deficiencies, requiring each vehicle to slow sharply while entering the visual inspection area; these systems also rely heavily on toll-taker attentiveness.
Additionally, a number of systems have been proposed for utilizing radio frequency identification (RFID) techniques for toll collection. Under these systems, drivers acquire a xe2x80x9ctagxe2x80x9d or card that acts as a reflective transmitter or discrete transmitter to identify the vehicle by serial number as it passes through a toll booth. This technique is also referred to as Automatic Vehicle Identification (AVI).
This system also suffers from a number of deficiencies. In particular, because the RFID tag lacks a machine-intelligent processor for manipulation and storage of accounts, toll authorities must maintain individual toll accounts for all users of the system. This becomes especially burdensome in urban areas or regions of high toll traffic volume. Toll agencies would need to manage hundreds of thousands of individual accounts, a burden that is created by operation of the AVI system.
Additionally, because the RFID tags lack a processor or user interface, vehicle operators cannot readily ascertain account balances, and have no warning as to limited or exhausted credit. This creates both confusion, and potential safety hazards, as drivers cross over to conventional toll collection lanes with little warning.
Further, in the absence of a single national toll agency, each participating driver would need to have multiple cards attached to the vehicle, each corresponding to a separate toll authority account.
The RFID system also raises user-privacy issues by requiring the generation and storage of detailed vehicle-specific travel records.
In response to the inability of conventional toll collection means to meet the demands created by increased highway traffic, automated toll facilities that provide improved toll collection methods and systems have been proposed. These automated toll facilities eliminate the manual transactions of conventional toll collection means through the use of radio transmitters and receivers that perform the necessary transactions as a vehicle travels through the automated toll booth. One such system electronically collects tolls from an electronic cache of toll credits carried within the vehicle. In this way, a vehicle operator can purchase a quantity of toll credits prior to traveling on a toll road. As the vehicle later travels through a toll collection booth, a radio-frequency exchange occurs and the appropriate amount is automatically debited from the vehicle""s toll credits.
Although the automated toll collection system described above functions well for single lane toll roads or single lane bridges and tunnels, a significant problem can exist when the system is practiced in a multi-lane environment. In a multi-lane environment, each toll lane is equipped with a stationary radio-transceiver to interact with the mobile radio-transceiver of vehicles passing through that lane. The problem of multi-pathing occurs when information transmitted from a vehicle in one lane is picked up by multiple toll lane stationary transceivers. Therefore the possibility exists that a toll collected from a vehicle in lane 1 may be credited to the vehicle in lane 2. The effect of multi-pathing allows toll-evaders to exploit automated toll systems, as well as accidentally misallocating the debits.
A number of prior art systems exist that minimize the effects of multi-pathing. These systems typically attempt to shield the toll transceiver of one lane from signals transmitted from mobile units traveling in an adjacent lane. Such systems include methods that establish a proximity zone that identifies when a vehicle has entered a predetermined region, and then requires the vehicle to transmit the toll within a predetermined time limit. Other systems establish a multi-field environment, where a blanking field is transmitted behind and adjacent to a region proximate to the toll lane. The blanking zone serves to swamp out any multi-path signals that could be received by the toll station. The prior art systems do not provide a means for determining the actual lane position of an oncoming mobile unit. Because of this, the prior art systems do not allow the toll system to determine the physical sequence of oncoming traffic approaching the toll system. Moreover, the prior art systems place constraints on the size of the lanes and the spacing that must exist between each lane transceiver.
It is accordingly an object of the invention to provide improved toll collection methods and apparatus that significantly increase the traffic capacity of roadways.
Another object of the invention is to provide toll collection methods and apparatus that increase the rate of toll collection while enhancing highway safety.
A further object of the invention is to provide such methods and apparatus that are convenient to use and support toll collection by a plurality of toll authorities or authorities at a plurality of widely separated locations.
Yet another object of the invention is to provide toll collection systems that reduce administrative burdens, facilitate the generation of transaction reports for users and toll authorities, and preserve the privacy of users.
It is a further object of the invention to provide toll collection systems that are reliable and resistant to attempts at fraud or toll evasion, and which are readily integrated into existing toll management systems.
Another object of the present invention is to provide a system for determining the lane position of a vehicle approaching an automated toll system.
A further object of the invention is to provide a mechanism for determining the sequence of mobile units approaching an automated toll system.
An additional object of the invention is to provide a system for determining the relative position of a mobile object approaching a stationary transceiver.
And yet another object of the invention is to provide a system for automatic toll collection that uses toll transceivers that can work in close proximity with other toll transceivers.
Other general and specific objects of the invention will in part be obvious and will in part appear hereinafter.
The foregoing objects are attained by the invention, which provides methods and systems for automatically collecting tolls from a vehicle moving at high speed along a roadway.
One aspect of the invention includes at least a first toll facility through which the vehicle can pass for toll collection, and an in-vehicle transponding toll processor having storage for storing a toll-money-available signal representative of a monetary quantity available for debiting in a toll transaction at an upcoming toll facility and a vehicle-specific identifier. Initially, the toll processor is loaded, for example, at a toll facility, with an electronic gross-toll-amount signal representative of an initial toll-money-available value.
A first toll-facility-identification site, corresponding to and remote from a first toll facility collection site, transmits a first toll-facility-identifier signal uniquely representative of (i) the location of the first toll facility and optionally also (ii) a toll schedule corresponding to the roadway. As the moving vehicle approaches the first toll-facility-identification site, the in-vehicle toll processor receives and stores the first toll-facility-identifier signal, and calculates, in response to the first toll-facility-identifier signal, a toll amount to be debited at the first toll facility.
In particular, the in-vehicle toll processor compares the calculated toll amount with the toll-money-available signal stored in the in-vehicle processor, to test whether the monetary quantity represented by the toll-money-available signal is greater than or equal to the calculated toll amount. The in-vehicle toll processor preferably responds to a selected result of this comparison by providing the vehicle operator with a signal, such as a beep, or a beep accompanied by a flashing colored light, representative of permission to utilize the first automated toll facility.
Subsequently, as the vehicle approaches and passes through the first toll facility collection site, the first toll facility collection site transmits a toll-collect signal instructing the in-vehicle toll processor to debit the toll amount from its storage. The in-vehicle toll processor responds by debiting the calculated toll amount from its storage, reducing the value of the toll-money-available signal in accordance with the amount debited. Additionally, the in-vehicle toll processor transmits transaction acknowledgment signal indicating to the toll facility collection site its identification, the calculated toll amount and the account balance.
In another aspect of the invention, when the comparison executed by the in-vehicle toll processor indicates that the toll money available is less than the calculated toll amount, or is less than a preselected programmed minimum balance, such as twenty dollars, the in-vehicle toll processor responds by internally incrementing the balance, and activating a debit message to assure that the toll facility charges the new increment to a credit or billing agency, such as a bank account or credit card company.
A further aspect of the invention provides for operation on a progressive toll roadway, on which toll amounts depend upon where the vehicle enters and where it exits the tollway. In this aspect the invention includes at least a second toll facility remote from the first toll facility, with a second toll-facility-identification site corresponding to and remote from a second toll facility collection site. The second toll-facility-identification site transmits at least a second toll-facility-identifier signal uniquely representative of (i) the location of the second toll facility and preferably also (ii) the toll schedule corresponding to the roadway. As discussed further below, the toll schedule may be the schedule for all classes of vehicles for all exits, or may be the schedule for all vehicles entering or exiting at the particular site.
The in-vehicle toll processor receives the second toll-facility-identifier signal, and if the vehicle did not previously pass through the first toll collection facility, the in-vehicle toll processor overwrites the stored first toll-facility-identifier signal with the second toll-facility-identifier signal.
In one aspect of the invention, the toll-facility-identifier signals, the vehicle identifier and toll-transaction signals or acknowledgment signals are encoded radio-frequency signals, and the encoding can be dynamically varied to reduce the possibility of fraud, or to carry additional selected information.
Precise identification of the position of a vehicle as it passes a toll station is achieved in one aspect of the invention, which includes at least one stationary transceiver unit positioned above one lane of a multi-lane roadway that transmits an identification signal in a known field pattern. A mobile transceiver unit traveling along the multi-lane roadway receives the identification signal and decodes the identity of the stationery transceiver unit and evaluates the strength of the signal. From this information, the mobile transceiver determines its position with respect to the stationery transceiver unit.
In particular, at least one stationery transceiver unit is positioned above one lane of a multi-lane roadway. The transceiver includes a highly directional antenna that transmits a radio-frequency signal. The signal is directed along the roadway and in the direction of oncoming traffic. The directional signal broadcast from the antenna sets up a field pattern within one lane of the multi-lane roadway. By encoding the signal with information that identifies the lane in which the antenna is directed, a radio-frequency field can be set up that uniquely identifies one lane of the roadway.
A vehicle equipped with a transceiver made in accordance with the present invention can determine its lane of travel and its distance from the stationery transceiver by receiving and processing the antenna field pattern. The mobile transceiver, fixed within a vehicle such as an automobile, receives signals generated by the stationery transceivers. The mobile transceiver then decodes these signals and determines from which lane the signal was broadcast. The mobile transceiver then associates with each lane identity a signal strength that can be compared to the known field pattern of the stationery transceiver directional antenna. The mobile transceiver processes the signal strength and signal identity and determines its location relative to the stationery transceiver.
Subsequently, as the vehicle passes the stationery transceiver units, it transmits its vehicle identification number and its lane position so that the stationery transceivers know which vehicle is passing in which lane.
The invention will next be described in connection with certain illustrated embodiments; however, it should be clear to those skilled in the art that various modifications, additions and subtractions can be made without departing from the spirit or scope of the claims.